||This Saturn I is displayed at the US Space and Rocket Center in Huntsville, Alabama. It differs from the Saturn IB by its smaller second stage (which uses a cluster of six Pratt & Whitney RL-10 engines rather than one Rocketdyne J-2) and the shape of the eight tail fins. The spacecraft adapter on top of the second stage is also different from the Spacecraft-Lunar Module Adapter (SLA) used on the Saturn IB and Saturn V. I have no information as to the identity of the spacecraft on top of this booster: it possibly is JSC #4 or one of two boilerplates assigned to the next-door Marshall Space Flight Center.
The paint scheme on this booster does not correspond to any flown vehicles. The checkerboard pattern was found on SA-5 which did not fly with a spacecraft as payload. Those with spacecraft used a roll pattern that is similar to that on the S-IVB on the Saturn IB, although reversed. The roll pattern on the fins is also off, as the black-white boundary should be horizontal to the ground an bisecting the root edge of the fins. It also appears that the painted area extend through the whole quadrant.